new American Hymenoptera. 211 
Nomada aztecorum, sp. n. 
? .—Length 11 millim. or rather more. 
Black, with bright yellow markings. Head broad, but 
facial quadrangle not far from square ; anterior half of clypeus, 
not extending to sides, yellow; yellow lateral face-marks 
broad below, narrowing upwardly to form a band on orbital 
margins reaching above level of antenne as far as two thirds 
length of scape ; no yellow below eyes, on cheeks, on labrum, 
or mandibles, but the latter have a ferruginous mark; a very 
small yellowish-red dot at summit of each eye; mandibles 
simple; labrum densely punctured, with a median smooth 
band, slightly elevated on the margin; face and front densely 
punctured ; first three joints of antenne (except the apical 
half of scape above) and apex of last joint bright red, the rest 
black, in strong contrast; third antennal joint barely longer 
than fourth ; thorax extremely densely punctured, especially 
the dull mesothorax ; margin of prothorax above, tubercles, 
spot on pleura, two pear-shaped spots on scutellum, post- 
scutellum, and two very small spots on metathorax yellow ; 
scutellum not bilobed ; tegulz bright ferruginous, punctured. 
Wings strongly smoky, especially on apical margin; stigma 
dark reddish, nervures piceous; third submarginal cell un- 
usually broad above; transverso-medial nervure meeting 
basal. Legs black and red, the tibiee and tarsi with light 
golden pubescence ; a spot on middle coxe and a very broad 
V on hind coxe yellow; femora largely black, tibie and 
tarsi red, the hind ones blackened behind; abdomen with a 
minute hardly noticeable punctuation, appearing rather as a 
minute roughening; black, with five yellow bands, the first 
narrowed to a point in the middle, the second narrowed about 
half; venter black, with two large yellow triangles, touching 
in the middle line, on second segment. 
Hab. Amecameca, Mexico, September (Barrett). 
Sent by Mr. Viereck, who received it trom Mr, Titus. A 
very fine and distinct species. 
Nomada Vierecki, sp. n. 
9.—Length about 7 millim. 
Black and ferruginous, marked with cream-colour; man- 
dibles simple; third antennal joint longer than fourth; trans- 
verso-medial nervure entering the end of the externo-medial. 
This has been erroneously recorded as N. modesta, but it 
differs conspicuously as follows :—Size smaller; light mark- 
ings cream-colour instead of yellow; no light ae on meta- 
